The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Isolated switching power converters typically include a transformer, one or more primary switches coupled to a primary winding of the transformer, and an output capacitor, inductor and rectifier coupled to a secondary winding of the transformer. For example, the full-bridge power converter 100 in FIG. 1 includes a transformer TX1 having a primary side including a primary winding 110 and a secondary side including a secondary winding 120. Primary switches Q1-Q4 are connected to the primary side for switching an input voltage Vin across the primary winding 110. On the secondary side, the secondary winding 120 is connected to an output inductor L1, output capacitor C1 and a pair of synchronous rectifiers Q5, Q6. The output inductor L1 stores and release energy and operate as a filter choke in the power converter 100. Because primary switches Q1-Q4 typically switch on and off with a voltage across them, losses occur during switching. Additionally, the synchronous rectifiers Q5, Q6 each include a body diode 130. Current flowing through the synchronous rectifiers Q5, Q6 when they turn off causes the body diode 130 to conduct, leading to reverse recovery voltage spikes on the synchronous rectifiers Q5, Q6. The switches, commonly MOSFETs, for the synchronous rectifiers Q5, Q6 are generally chosen for, among other things, their ability to withstand high voltage of the reverse recovery voltage spikes.